Chopawamsic Formation - Foliated felsite

Light-gray to white, medium-grained, foliated felsite ranges in composition from rhyolite to dacite. Mineralogy: quartz + perthitic microcline + muscovite + biotite; beta-form quartz phenocrysts are characteristic.
State Virginia
Name Chopawamsic Formation - Foliated felsite
Geologic age Cambrian
Lithologic constituents
Major
Igneous > Volcanic > Felsic-volcanicLight-gray to white, medium-grained, foliated felsite ranges in composition from rhyolite to dacite.
Comments Central Virginia Volcanic-Plutonic Belt
References

Virginia Division of Mineral Resources, 1993, Geologic Map of Virginia: Virginia Division of Mineral Resources, scale 1:500,000.

Virginia Division of Mineral Resources, 2003, Digital Representation of the 1993 Geologic Map of Virginia, Publication 174, CD ROM (ISO-9660) contains image file, expanded explanation in pdf, and ESRI shapefiles, scale 1:500,000.

NGMDB product
Counties Fluvanna - Goochland